docs: def resolve_path(filename: Path) -> typing.Union[Path, None]:
      """Find a file by walking up parent directories until the file is found.
      Return the absolute path of the file.
      """
      current = Path.cwd()
      # Stop search at home directory
      sentinel_dir = Path.home().parent.resolve()
      while current != sentinel_dir:
          target = Path(current) / Path(filename)
          if target.exists():
              return target.resolve()
          else:
              current = current.parent.resolve()
  
      return None